1. Field of the Invention
This invention relates to an image information processing system, and more particularly to an image information processing system which electrically deals with image information and can accomplish recording and storage of images or transmission or the like of image information between it and other apparatus.
2. Description of the Prior Art
In recent years, in the field of the office automation, the demand has become strong for an image information processing system which electrically deals with image information such as pictures, figures and photographs in the same manner as that in which documents are dealt with and which can store electrical image information or can accomplish the exchange of image information between it and other apparatus through a communication network or the like, and the market has seen the advent of apparatuses of such type.
In an apparatus of such type, an original is set on an input device such as an image scanner for inputting image information, the input device reads the image information from the original, and the read image information is suitably compressed and stored in a memory such as an optical file or transmitted to other apparatus.
The apparatus for reproducing this data or the apparatus having received the transmitted data has expanded the sent image information on a recording sheet set on an output device such as a laser beam printer, as required, and then has printed and put out the image.
Generally, an image data comprising a mixture of characters, figures, photographs, etc. is enormous in amount as compared with an image data comprising characters only. Accordingly, if it is digitally stored, the memory capacity becomes great and also, when the data is to be transmitted to an external apparatus at a limited transmission speed, a long time will be required to transmit even an image data corresponding to one page. So, the image data thinning/insertion method is often used for this purpose.
Heretofore, as seen in a facsimile apparatus or the like, the thinning/insertion control in the main scanning and sub scanning has been effected. For example, characters and figures are read while being thinned for each predetermined line in the sub scanning direction and are false-reproduced on the reception side. However, where half-tone images such as photograph images have been read while being thinned, the images false-reproduced on the reception side are sometimes not good half-tone images, and this method has not been very preferable for half-tone images. Also, this thinning function can be alternatively selected for an image (an original) and can no longer be displayed where an image comprises a mixture of characters, figures, photographs, etc.
Also, the image data encoding compression/expansion method is often used as a method of decreasing the amount of image data to be transmitted or stored without executing the above-described image data thinning process. The run length method or the modified Hoffmann (MH) method is often used as a method which is simple in construction and can obtain a good compression/expansion ratio, but these methods are suitable for the compression of character and figure data in which white or black binary data continues and are not suitable for data such as photographs having half-tones.
Therefore, various types of apparatus have heretofore been constructed by usage and, for example, the type of apparatus exclusively for use for figures or the type of apparatus exclusively for use for photographs has been prepared. Accordingly, if photographs are transmitted by the type of apparatus exclusively for use for characters and figures which is simple in construction and can obtain a relatively high compression/expansion ratio, the intended performance cannot be displayed, and if characters and figures are transmitted by the type of apparatus exclusively for use for photographs which is expensive, the intended performance cannot be displayed and in addition, it is uneconomical. Much less, where the image to be transmitted comprises a mixture of characters and photographs, it is actually difficult to imagine what degree of compression/expansion ratio can be obtained, and if encoding compression is applied to photograph data rather by the run length method, there has been a disadvantage that the data becomes rather great.
Also, in a case where an image data is to be transmitted to other output device placed at a remote place and the image is to be recorded on a recording sheet by that output device or in a case where an image data already stored in an image file is to be read out and the image is to be reproduced, if the size of the recording sheet set on the output device is not coincident with the size of the input original, it is possible in the case of a document original to enlarge or reduce the image information and thereby adjust the size thereof to the size of the recording sheet, but in the case of a figure or a photograph which requires a high resolution, the original image cannot be made to correspond to the recorded image by the enlarging/reducing process and the recorded image becomes very difficult to see. Therefore, where the size of the input original is not coincident with the size of the recording sheet, the image information cannot be put out by the output device and thus, the transmission of the image information has become wasteful.
Particularly, where image information communications are to be effected between Japan and a foreign country, for example, the United States of America, the standard paper sizes differ between the two countries and it is wasteful to prepare all these paper sizes.